Pauropoda are tiny multipedes less than 2 mm long. Species identification is very difficult, as you need to examine specially prepared specimens under a microscope at high magnification.
Nineteen native pauropod species have been described from Tasmanian rainforest (Coy et al. 1993, Greenslade 2008, Scheller 2009; see checklist for names), and there may also be introduced species living in gardens. Of our natives, Scheller (2009, p. 328) writes:
Pauropods depend upon sustained conditions of moisture and humidity in their living space and are normally true soil dwellers adapted to a uniform type of environment. However, in humid climates, they sometimes, at least temporarily, inhabit lower litter layers and can be found under moss and under bark of rotting wood. By using different collecting techniques in Tasmanian rainforest and by careful handling of the material, it has appeared that pauropods are unexpectedly abundant in moss and are probably living in the contact zone between the moss and underlying soil or log. They were also found in habitats not previously considered to be inhabited by pauropods such as on tree trunks (Greenslade, 2008). The record of both adults and juveniles of Stylopauropoides quadripartitus sp. nov. in the crown of a tree fern indicates that reproduction was occurring in this habitat.
Below: a European pauropod ca 0.9 mm long. Image courtesy Andy Murray through Flickr.
Symphyla are small, blind, fast-running multipedes which can be abundant in soil and forest litter. They are generally white, but dark-coloured gut contents can often be seen through the body wall. As with Pauropoda, species identification is difficult: the important characters can only be seen under a microscope at high magnification.
Eight of the nine described Tasmanian species (see checklist) were collected during a survey of Tasmanian rainforest (Coy et al. 1993, Rushton 1990). Symphyla are often common in other forest types, and one Tasmanian cave species, Hanseniella magna, is said to be the largest Symphyla ever collected (Scheller 1996). Large cave forms (to 10 mm in body length) have also been found in the Junee-Florentine karst.
Tasmanian Symphyla were apparently first noted more than 180 years ago by Henry Hellyer, a surveyor and naturalist employed by the Van Diemen's Land Company. Hellyer was supervising the cutting of a track (later to become Old Surrey Road) in the Emu River valley near Burnie. The track passed through old-growth eucalypt forest with numerous rotting logs and a thick litter layer. On 13 July 1827 Hellyer recorded seeing 'young centipedes white as snow', which were almost certainly Symphyla and which are still abundant in the Emu Valley forest.
The image below shows Hanseniella ?audax from the Dial Range in NW Tasmania. Body length is ca 8 mm.